Fuel Injector: Testing and Inspection

Fig. 65 Fuel injector testing:

1. Disconnect electrical connector from injector and measure resistance between injector terminals. Resistance should be 1.5 to 3.0 ohms.
2. Remove delivery pipe and injector assembly, taking care not to drop injectors.
3. Using adapter hoses and holder 092168-41045 and 09842-30011, install each injector between pressure regulator and fuel filter as shown in Fig. 65.
4. Turn ignition on but do not start engine, then connect jumper wire between fuel pump check connector terminals. Injector should not drip fuel.
5. Apply battery voltage to injector for 15 seconds and measure amount of fuel collected in graduated cylinder. Care must be taken to avoid producing sparks during injector test. Install suitable vinyl tube over injector nozzles to prevent fuel from splashing out of container.
6. On all except 3S-GE, 4A-GE, 4A-GEC, 4A-GEL, 4A-GELC, 7M-GE, 7M-GTE engines, each injector should issue 40---50cc of fuel in 15 seconds, and the maximum difference between injectors should be less than 6cc. On 3S-GE, 4A-GE, 4A-GEC, 4A-GEL and 4A-GELC engines, each injector should issue 49---56cc of fuel in 15 seconds, and the maximum difference between injectors should be less than 5cc. On 7M-GE engines, each injector should issue 65---80cc of fuel in 15 seconds, and the maximum difference between injectors should be less than 5cc. On 7M-GTE engines, each injector should issue 101---114cc of fuel in 15 seconds, and the maximum difference between injectors should be less than 5cc.
7. Repair or replace injectors that do not operate as specified.
8. Disconnect injector from battery and ensure injector does not leak more than one drop per minute.
9. Install injector and delivery pipe assembly using new O-rings.